hvc_xen: introduce HVC_XEN_FRONTEND

Introduce a new config option HVC_XEN_FRONTEND to enable/disable the
xenbus based pv console frontend.

Signed-off-by: Stefano Stabellini <stefano.stabellini@eu.citrix.com>
Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>

diff --git a/drivers/tty/hvc/Kconfig b/drivers/tty/hvc/Kconfig
index 4222035acfb71987a7f3f7c50db32cd5aae87262..192e21e2239c6547708c0f9c97061adcb24d5390 100644 (file)
--- a/drivers/tty/hvc/Kconfig
+++ b/drivers/tty/hvc/Kconfig
@@ -76,6 +76,14 @@ config HVC_XEN
        help
          Xen virtual console device driver
 
+config HVC_XEN_FRONTEND
+       bool "Xen Hypervisor Multiple Consoles support"
+       depends on HVC_XEN
+       select XEN_XENBUS_FRONTEND
+       default y
+       help
+         Xen driver for secondary virtual consoles
+
 config HVC_UDBG
        bool "udbg based fake hypervisor console"
        depends on PPC && EXPERIMENTAL

diff --git a/drivers/tty/hvc/hvc_xen.c b/drivers/tty/hvc/hvc_xen.c
index 26090c736bcfe0f9ec7d0caa4e8a8899ac8f3feb..83d5c88e7165d5a95cc743812a6075fa7a0ff621 100644 (file)
--- a/drivers/tty/hvc/hvc_xen.c
+++ b/drivers/tty/hvc/hvc_xen.c
@@ -55,7 +55,6 @@ struct xencons_info {
 
 static LIST_HEAD(xenconsoles);
 static DEFINE_SPINLOCK(xencons_lock);
-static struct xenbus_driver xencons_driver;
 
 /* ------------------------------------------------------------------ */
 
@@ -298,53 +297,6 @@ static int xen_initial_domain_console_init(void)
        return 0;
 }
 
-static int __init xen_hvc_init(void)
-{
-       int r;
-       struct xencons_info *info;
-       const struct hv_ops *ops;
-
-       if (!xen_domain())
-               return -ENODEV;
-
-       if (xen_initial_domain()) {
-               ops = &dom0_hvc_ops;
-               r = xen_initial_domain_console_init();
-               if (r < 0)
-                       return r;
-               info = vtermno_to_xencons(HVC_COOKIE);
-       } else {
-               ops = &domU_hvc_ops;
-               if (xen_hvm_domain())
-                       r = xen_hvm_console_init();
-               else
-                       r = xen_pv_console_init();
-               if (r < 0)
-                       return r;
-
-               info = vtermno_to_xencons(HVC_COOKIE);
-               info->irq = bind_evtchn_to_irq(info->evtchn);
-       }
-       if (info->irq < 0)
-               info->irq = 0; /* NO_IRQ */
-       else
-               irq_set_noprobe(info->irq);
-
-       info->hvc = hvc_alloc(HVC_COOKIE, info->irq, ops, 256);
-       if (IS_ERR(info->hvc)) {
-               r = PTR_ERR(info->hvc);
-               spin_lock(&xencons_lock);
-               list_del(&info->list);
-               spin_unlock(&xencons_lock);
-               if (info->irq)
-                       unbind_from_irqhandler(info->irq, NULL);
-               kfree(info);
-               return r;
-       }
-
-       return xenbus_register_frontend(&xencons_driver);
-}
-
 void xen_console_resume(void)
 {
        struct xencons_info *info = vtermno_to_xencons(HVC_COOKIE);
@@ -392,6 +344,9 @@ static int xen_console_remove(struct xencons_info *info)
        return 0;
 }
 
+#ifdef CONFIG_HVC_XEN_FRONTEND
+static struct xenbus_driver xencons_driver;
+
 static int xencons_remove(struct xenbus_device *dev)
 {
        return xen_console_remove(dev_get_drvdata(&dev->dev));
@@ -543,6 +498,65 @@ static const struct xenbus_device_id xencons_ids[] = {
 };
 
 
+static DEFINE_XENBUS_DRIVER(xencons, "xenconsole",
+       .probe = xencons_probe,
+       .remove = xencons_remove,
+       .resume = xencons_resume,
+       .otherend_changed = xencons_backend_changed,
+);
+#endif /* CONFIG_HVC_XEN_FRONTEND */
+
+static int __init xen_hvc_init(void)
+{
+       int r;
+       struct xencons_info *info;
+       const struct hv_ops *ops;
+
+       if (!xen_domain())
+               return -ENODEV;
+
+       if (xen_initial_domain()) {
+               ops = &dom0_hvc_ops;
+               r = xen_initial_domain_console_init();
+               if (r < 0)
+                       return r;
+               info = vtermno_to_xencons(HVC_COOKIE);
+       } else {
+               ops = &domU_hvc_ops;
+               if (xen_hvm_domain())
+                       r = xen_hvm_console_init();
+               else
+                       r = xen_pv_console_init();
+               if (r < 0)
+                       return r;
+
+               info = vtermno_to_xencons(HVC_COOKIE);
+               info->irq = bind_evtchn_to_irq(info->evtchn);
+       }
+       if (info->irq < 0)
+               info->irq = 0; /* NO_IRQ */
+       else
+               irq_set_noprobe(info->irq);
+
+       info->hvc = hvc_alloc(HVC_COOKIE, info->irq, ops, 256);
+       if (IS_ERR(info->hvc)) {
+               r = PTR_ERR(info->hvc);
+               spin_lock(&xencons_lock);
+               list_del(&info->list);
+               spin_unlock(&xencons_lock);
+               if (info->irq)
+                       unbind_from_irqhandler(info->irq, NULL);
+               kfree(info);
+               return r;
+       }
+
+       r = 0;
+#ifdef CONFIG_HVC_XEN_FRONTEND
+       r = xenbus_register_frontend(&xencons_driver);
+#endif
+       return r;
+}
+
 static void __exit xen_hvc_fini(void)
 {
        struct xencons_info *entry, *next;
@@ -580,12 +594,6 @@ static int xen_cons_init(void)
        return 0;
 }
 
-static DEFINE_XENBUS_DRIVER(xencons, "xenconsole",
-       .probe = xencons_probe,
-       .remove = xencons_remove,
-       .resume = xencons_resume,
-       .otherend_changed = xencons_backend_changed,
-);
 
 module_init(xen_hvc_init);
 module_exit(xen_hvc_fini);